This invention relates to a load control device for use with a vehicle restraint system. Several pertinent references, the disclosures of which are incorporated herein by reference, include U.S. Pat. Nos. 5,961,060; 5,967,442, and 6,564,895.
The present invention comprises one or more of the features identified in the various claims appended to this application and combinations of such features as well as one or more of the following features or combinations thereof. One illustrative load control device comprises a frame or housing, a spool carried by the frame or housing and movable therein, a load limiting member or torsion bar coupled to the spool and fixed against movement relative to the spool, and a stop member coupled to the load limiting member and fixed against movement relative to the load limiting member. The frame or housing defines a cavity having opposing holes or openings through which the spool may be received. The cavity is sized so that the spool may move freely therein. The frame or housing has a longitudinal axis through the center of the cavity. The spool has a central bore formed therethrough. The central bore has a longitudinal axis which is generally aligned with the longitudinal axis of the frame when the spool is received within the frame's cavity. The central bore may be formed in any geometrical shape such as for example and without limitation an ellipse, an oval, a triangle, a square, a rectangle, a parallelogram, a pentagon, a hexagon, an octagon or other suitable shape. At least a portion of the load limiting member is formed and sized to be received within the bore such that the load limiting member and spool are substantially fixed from movement relative to one another. At least a portion of the load limiting bar is formed and sized to couple with the stop member such that the stop member and load limiting member are fixed from movement relative to one another. Thus, when the stop member and the load limiting member are coupled together, and the load limiting member is received within the bore, the stop member, the load limiting member and the spool are each fixed from appreciable movement with respect to one another. Illustratively, the load limiting member's opposing ends may be those portions formed to fit within the bore and couple to the stop member. These opposing ends may have the same size and shape such that either end will fit into either the bore or the stop member and fix movement of the load limiting member relative thereto. The frame may be formed with one or more protrusions or tabs, which couple with voids on the stop member. In the alternative, the stop member may have one or more protrusions or tabs which couple with voids formed in the frame or housing. In any event, when the load limiting member is received within the bore and coupled with the stop member, which in turn is coupled with the frame, then the spool, the load limiting member, and the stop member are all fixed from movement relative to the frame or housing. When so assembled, the load limiting member and the bore each define a longitudinal axis through their centers that is generally co-axial with the longitudinal axis of the other and with the longitudinal axis of the cavity of the frame or housing. A length of a flexible or semi-flexible restraint member, such as a web, may be wound about the spool prior to coupling the stop member to the frame or housing. Such a web may form a part of an occupant restraint system carried by a vehicle. In the event of a deceleration of sufficient force or magnitude, the load limiting member will deform, allowing the pre-wrapped web to pay out in order to limit or reduce the force of the deceleration experienced by the occupant.
Another illustrative load control device comprises at least one mounting member or frame fastened to a load limiting member or frame. In the alternative, a pair of spaced apart mounting members or frames may sandwich therebetween a load limiting member. In any event the mounting member(s) is/are oriented generally transversely to the load limiting member. The load limiting member may have an inverted generally T-shaped profile. The mounting member(s) define a pair of anchor slots each formed to receive therethrough a flexible or semi-flexible restraint member, such as for example a web belt or strap. The anchor slots may be closed or may have an opening through the frame configured to allow a web to be inserted into or removed from the respective anchor slot. Each mounting member or frame further defines one or more cavities formed to receive a stop member, coupler, guide, or fastener, such as for example and without limitation a rivet. The load limiting member defines therethrough a generally longitudinally oriented and variable sized anchor slot or load limiting channel and a generally transversely oriented lower anchor slot separate from and generally perpendicular to the load limiting channel or slot. The variable sized load limiting channel or slot may be wider at the bottom or proximate end of the slot and sized to receive therethrough the fasteners or couplers. The load limiting channel or slot narrows above the fasteners, such that during normal operating conditions the fasteners are substantially fixed from linear movement away from the proximate end relative to the load limiting member. The fasteners pass through the cavities or hole(s) of one mounting member, through the lower portion of the load limiting channel or slot and through the cavities or hole(s) of the other slot in order to fasten together the plates and the inverted T-shaped member. Restraint members or webs may then be passed through each of the three anchor slots, such as for example on an add-on child restraint system or device, such as for example a portable child seat. For example, a pair of shoulder restraint members could be inserted through the pair of anchor slots in each frame and routed up the back of a child seat, and a lower restraint member or crotch strap or web could be inserted into the lower anchor slot of the load limiting member and routed under the seat to a crotch strap, or even anchored to the child seat. A conventional restraint system could comprise the shoulder belts, which could be used to secure an occupant into the child seat. The child seat could be mounted in a vehicle. Then, in the event that the vehicle experiences a dynamic event or occurrence like a deceleration of predetermined magnitude, such as in the event of an impact with another vehicle, or some other abnormal event, the occupant will be thrown or urged against the should straps, which will elongate a certain amount. Thereafter, the shoulder belts will act against the mounting member frame and its anchor slot(s), while the lower belt will act in an opposite direction against the load limiting member and its anchor slot(s). Eventually, the load will be great enough and the fastener(s) or coupler(s) will move into the narrow portion of the load limiting channel or anchor slot and travel generally linearly therein as the channel yields or plastically deforms. The deformation of the sides of the load limiting channel and the generally linear travel of the fastener(s) or coupler(s) within the channel or slot control, limit or reduce the load or deceleration forces experienced by the occupant.
Another illustrative load control device comprises a frame defining therein one or more restraint member anchor slots and a load limiting member. The load limiting member may be an elongated member such as a bar. The anchor slots may receive one or more restraint members, which may be wrapped or looped around the load limiting member. When a load in excess of a predetermined load is applied to the anchor slots, the load limiting member will yield or deform.
A method of limiting the load from a dynamic event on an occupant of an add-on child restraint system having a restraint harness may comprise the step of threading the restraint harness through a load control device. An additional step may include allowing at least a portion of the load control device to yield or deform under a load.
Yet another illustrative load control device comprises a body member defining an aperture configured to receive a first web therethrough. A first web retainer arm extends from the body member and terminates at a first free end. The first web retainer arm and the body member form a first channel therebetween configured to receive a second web. A second web retainer arm extends from the body member and terminates at a second free end. The second web retainer arm and the body member form a second channel therebetween configured to receive a third web. A limit member may extend from the body member, and is configured to limit travel of the first and second web retainer arms in a direction away from the body member resulting from forces applied to the first and second web retainer arms by the second and third webs respectively.
The limit member may terminate at a distal end with the first and second free ends normally positioned between the body member and the distal end, the distal end of the limit member configured to come into contact with the first and second free ends to thereby limit travel of the first and second web retainer arms as they travel away from the body member. The distal end of the limit member may define a first stop member extending away from the distal end with the first free end of the first web retainer arm positioned between the body member and the first stop member. The distal end of the limit member may define a second stop member extending away from the distal end with the second free end of the second web retainer arm positioned between the body member and the second stop member.
The limit member and the first free end of the first web retainer arm may define therebetween a web access opening to the first channel. The first channel may slope away from the web access opening to the first channel to a terminal end of the first channel. The limit member and the second free end of the second web retainer arm may define therebetween a web access opening to the second channel. The second channel may slope away from the web access opening to the second channel to a terminal end of the second channel.
The first free end of the first web retainer arm may define a protrusion extending into the first channel and configured to facilitate retention of the second web within the first channel. The second free end of the second web retainer arm may likewise define a protrusion extending into the second channel and configured to facilitate retention of the third web within the second channel.
The body member, the first web retainer arm, second retainer arm, and limit member may be of uniform construction. The body member, first web retainer arm, second retainer arm, and limit member may together form a planar structure.
The components of the illustrative load control devices may be fashioned from any suitable metallic, non-metallic, or composite material.